partner-contact/partner_contact_nationality/models/res_partner.py

# Copyright (C) 2014-2015  Grupo ESOC <www.grupoesoc.es>
# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).

from odoo import fields, models


class ResPartner(models.Model):
    _inherit = 'res.partner'

    nationality_id = fields.Many2one("res.country", "Nationality")